Image pickup apparatus that compensates for flash band, control method therefor, storage medium, and video processing apparatus

ABSTRACT

An image pickup apparatus which satisfactorily compensates for a flash band appearing due to an external flash and prevents a row insensitive to the flash from appearing in a corrected image. The flash band appearing in a plurality of frames consecutive in terms of time is detected based on an image signal output from an image pickup device which sequentially starts exposure and sequentially reads out signals for each row of pixels. An image in at least one of those frames is corrected to a full-screen flash image. When a width of the flash band is smaller than the number of rows in one frame, a row in which the flash band does not appear is interpolated using a row in which the flash band appears and which immediately precedes or immediately succeeds the row in which the flash band does not appear.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of application Ser. No. 15/615,993,filed Jun. 7, 2017, the entire disclosure of which is herebyincorporated by reference.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates to an image pickup apparatus such as adigital single-reflex camera, a digital still camera, or a digital videocamera, a control method therefor, a storage medium, and a videoprocessing apparatus, and in particular, to improvements in flash bandcompensation technique of the image pickup apparatus.

Description of the Related Art

Some image pickup apparatuses such as a digital camera have a rollingshutter image pickup device which sequentially starts exposure andsequentially reads out signals in each row of pixels. Such image pickupapparatuses have a problem that a flash band that creates differentlevels of luminance appears in an image in one frame due to an externalflash because exposure timing and readout timing vary with rows.Conventionally, there has been proposed a flash band compensationtechnique for use in a case where a width of a flash band, which appearswhile an electronic shutter of an image pickup device is in use, issmaller than the number of rows in one frame (Japanese Laid-Open PatentPublication (Kokai) No. 2014-197822).

According to Japanese Laid-Open Patent Publication (Kokai) No.2014-197822 above, however, a flash band is detected based on an outputsignal from the image pickup device, and based on a result of thedetection, the way of driving the image pickup device is changed tocompensate for the flash band, it is necessary to configure a feedbackcircuit shorter than one frame, and this is hard to implement.

SUMMARY OF THE INVENTION

The present invention provides an image pickup apparatus with a flashband compensation technique which, even when a width of a flash bandappearing due to an external flash is smaller than the number of rows inone frame, satisfactorily compensates for the flash band to prevent arow insensitive to the flash from appearing in a corrected image, acontrol method therefor, a storage medium, and a video processingapparatus.

Accordingly, the present invention provides an image pickup apparatuscomprising an image pickup device configured to sequentially startexposure and sequentially read out signals for each row of pixels, adetection unit configured to, based on an image signal output from theimage pickup device, detect a flash band that appears in a plurality offrames consecutive in terms of time due to an external flash, acorrection unit configured to correct an image in at least one of theplurality of frames in which the flash band was detected by thedetection unit to a full-screen flash image, and a determination unitconfigured to determine whether a width of the flash band detected bythe detection unit is equal to or greater than the number of rows in oneframe, wherein when the determination unit determines that the width ofthe flash band is not equal to or greater than the number of rows in oneframe, the correction unit interpolates a row in which the flash banddoes not appear using a row in which the flash band appears and whichimmediately precedes or immediately succeeds the row in which the flashband does not appear.

According to the present invention, even when a width of a flash bandappearing due to an external flash is smaller than the number of rows inone frame, the flash band is satisfactorily compensated for to prevent arow insensitive to the flash from appearing in a compensated image.

Further features of the present invention will become apparent from thefollowing description of exemplary embodiments (with reference to theattached drawings).

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram schematically showing a control system of adigital video camera that is a first embodiment of an image pickupapparatus according to the present invention.

FIG. 2 is a view useful in explaining an output image in a case where anexternal flash is fired from a strobe or the like.

FIG. 3 is a diagram showing enlarged exposure time periods in a frame 1and a frame 2 in FIG. 2.

FIGS. 4A and 4B are diagrams useful in explaining an example in which animage in which a flash band was detected is corrected to a full-screenflash image by an image correction unit.

FIG. 5 is a flowchart useful in explaining an interpolation process fora frame boundary row in which no flash band appears.

FIG. 6 is a flowchart useful in explaining an interpolation process fora frame boundary row in which no flash band appears in a digital videocamera that is a second embodiment of an image pickup apparatusaccording to the present invention.

FIG. 7 is a flowchart useful in explaining an interpolation process fora frame boundary row in which no flash band appears in a digital videocamera that is a third embodiment of an image pickup apparatus accordingto the present invention.

DESCRIPTION OF THE EMBODIMENTS

Hereafter, embodiments of the present invention will be described withreference to the drawings.

FIG. 1 is a block diagram schematically showing a control system of adigital video camera that is a first embodiment of an image pickupapparatus according to the present invention.

Referring to FIG. 1, a lens unit 101 has a focusing mechanism, adiaphragm mechanism, an ND filter, a zoom mechanism, and so forth. Animage pickup device 102 is comprised of a CMOS sensor or the like, whichsequentially starts exposure and sequentially reads out signals for eachrow of pixels, and photoelectrically converts a bundle of rays from asubject formed through the lens unit 101 into an electric signal andoutputs a video signal. An image obtaining unit 103 obtains imageinformation generated using the video signal output from the imagepickup device 102. It should be noted that the image obtaining unit 103includes an analog-digital front-end if an output from the image pickupdevice 102 is an analog signal.

A flash band detecting unit 104 detects whether or not a flash band,which appears in a plurality of frames consecutive in terms of time dueto an external flash fired from a strobe or the like, appears as a videosignal. When the flash band is detected by the flash band detecting unit104, the image correcting unit 105 corrects an image in which the flashband was detected, to a full-screen flash image.

A system control unit 106, which includes a CPU, a RAM, a ROM, and soforth, is responsible for controlling the entire camera, and forexample, sends and receives information to and from each block of thecamera, determines operation of the camera through user operation, andcontrols operation of each block. An image pickup device control unit107 drivingly controls the image pickup device 102. For example, theimage pickup device control unit 107 provides control to determine gainfor the image pickup device 102 and output vertical drive pulses VD tothe image pickup device 102 as well as to control shutter speed. Here,the shutter speed which means an exposure time of an electronic shutterof the image pickup device 102 is controlled by the image pickup devicecontrol unit 107 sending electric charge accumulation start timing andelectric charge readout timing to the image pickup device 102.

A lens control unit 108 controls the diaphragm mechanism, the focusingmechanism, the zoom mechanism, the ND filter, and so forth of the lensunit 101. A recording/output unit 109 records a video signal, which hasbeen subjected to predetermined image correction, in a storage medium oroutputs the video signal to a display device such as a display.

Referring to FIGS. 2 to 4B, a description will be given of an exemplaryframe correction method for use when a flash band appears.

FIG. 2 is a view useful in explaining an output image in a case where anexternal flash is fired from a strobe or the like. In FIG. 2, thehorizontal axis represents time, and the vertical axis represents thenumber of rows in a vertical direction, and there is shown arelationship between a time at which an external flash is fired andimages that are output at this time. In FIG. 2, VD represents a verticaldriving pulse which is input to the image pickup device 102.

When a flash shorter than a time period corresponding to one row isfired at the time shown in FIG. 2, a frame 1 is being exposed to lightin a lower part of a screen, and a succeeding frame 2 is being exposedto light in an upper part of the screen. Thus, a flash band appears froma midpoint toward a bottom of the frame 1, and in the frame 2, a flashband appears in rows up to the same row as a row in which the flash bandappears in the frame 1.

Referring to FIGS. 3, 4A, and 4B, a description will be given ofproblems which arise when an electronic shutter that resets photodiodesof the image pickup device 102 while one frame is being exposed to lightis used. FIG. 3 is a diagram showing enlarged exposure time periods inthe frame 1 and the frame 2 in FIG. 2.

It is assumed that the electronic shutter is turned on at input of afirst HD (HD: horizontal driving signal), which is input at thebeginning of an exposure time period, so as to maximize the exposuretime period while the electronic shutter is kept on.

When a flash is fired from a strobe or the like for a very short timeperiod at the time shown in FIG. 3, the flash starts entering a row M+1in the frame 1, causing a flash band to appear. The flash enters theframe 2 up to a row M−1. The flash is supposed to enter a row M in theframe 2, but due to the electronic shutter being on during this timeperiod, no flash enters the row M, and hence a flash band appears inrows up to the row M−1. For this reason, a flash band corresponding tothe total number of rows N in one frame appears unless the electronicshutter is on, but since the electronic shutter is on, the number ofrows in which a flash band appears is smaller than the total number ofrows N in one frame.

Referring next to FIGS. 4A and 4B, a description will be given of anexample where an image in which a flash band was detected is correctedto a full-screen flash image by the image correcting unit 105. FIG. 4Ais a diagram schematically showing frames 1 and 2 in which a flash bandappears as shown in FIG. 2 and frames 0 and 3 immediately preceding andsucceeding the frames 1 and 2, respectively. As shown in FIG. 4A, tobring together the frame 1 and the frame 2 in which a flash band appearsinto one frame, a region A′ is obtained by substituting a region A inthe frame 0 for a region B in the frame 1. A region B′ is obtained bysubstituting the region B in the frame 1 for a region D in the frame 2.

Through this substitution, the frame 1 is corrected to a frame 1′ inwhich no flash band appears, and the frame 2 is corrected to a frame 2′in which a flash band appears all over the screen to generate an imageflashing all over the screen (full-screen flash image) in only oneframe.

However, as described above, when the electronic shutter is on, thenumber of rows in which the flash band appears is smaller than the totalnumber of rows in one frame. For this reason, when the frame 2′ is to begenerated, a row (boundary row) in which no flash band appears ispresent between the region C and the region B′ as shown in FIG. 4B, andhence a horizontal line appears in the full-screen flash image, which inturn causes discomfort.

Therefore, in the present embodiment, the boundary row in which no flashband appears in the full-screen flash image of the frame 2′, which isthe corrected image, is interpolated by, for example, using a last row(immediately preceding the boundary row) in the region C or a first row(immediately succeeding the boundary row) in the region B′. Thisprevents a horizontal line, which is a row insensitive to the flash,from appearing in the full-screen flash image.

Referring next to FIG. 5, a description will be given of aninterpolation process for a frame boundary row in which no flash bandappears. Processes in FIG. 5 are carried out by the CPU or the likeexecuting programs stored in the ROM or the like of the system controlunit 106 and expanded into the RAM.

Referring to FIG. 5, in step S501, the system control unit 106 causesthe flash band detecting unit 104 to judge whether or not a flash bandappears in a video signal. When the flash band appears, the systemcontrol unit 106 identifies a row in which the flash band appears, andthe process proceeds to step S502. In the step S502, the system controlunit 106 causes the image correction unit 105 to perform the flash bandcompensation described above with reference to FIG. 4A to generate afull-screen flash image, and the process proceeds to step S503.

In the step S503, the system control unit 106 judges whether or not theelectronic shutter of the image pickup device 102 was turned on for aframe in which the flash band was detected. When the electronic shutterwas not turned on, the system control unit 106 determines that the flashband was successfully compensated for to obtain the full-screen flashimage in the step S502, and ends the process. When the system controlunit 106 judges that the electronic shutter was turned on, the processproceeds to step S504. It should be noted that in the step S503, whetheror not the electronic shutter was on should not necessarily be judged,but whether or not a flash band corresponding to the total number ofrows in one frame appears may be judged when rows in which the flashband appears are identified in the step S501.

In the step S504, since a row in which no flash band appears should bepresent at a frame boundary in the full-screen flesh image obtained inthe step S502, the system control unit 106 causes the image correctionunit 105 to carry out an interpolation process for this boundary row andends the process. It should be noted here that the interpolation processadopted here is carried out using a simple method that involves copyingthe last row in the region C or the first row in the region B′ to therow in which no flash band appears as described earlier with referenceto FIG. 4B, but the way to carry out the interpolation process is notlimited to this. For example, interpolation may be performed byaveraging the last row in the region C and the first row in the regionB′ in FIG. 4B or by obtaining a weighted average using more rows thanthose two rows.

As described above, in the present embodiment, even when a width of aflash band resulting from an external flash is smaller than the totalnumber of rows in one frame due to, for example, turning-on of theelectronic shutter, the flash band is satisfactorily compensated for toprevent a row insensitive to the flash from appearing in a correctedimage.

Referring next to FIG. 6, a description will be given of a digital videocamera that is a second embodiment of the image pickup apparatusaccording to the present invention. It should be noted that for elementscorresponding to those of the first embodiment described above, the samefigures and reference symbols are used in the following description ofthe present embodiment.

In the first embodiment described above, whether or not to interpolate aframe boundary row in which no flash band appears is judged according towhether or not the system control unit 106 judges whether or not theelectronic shutter of the image was turned on, but a full-screen flashimage may cause increased discomfort, depending on a position of theelectronic shutter. For this reason, in the present embodiment, controlis provided so as not to interpolate a frame boundary row in which noflash band appears.

FIG. 6 is a flowchart useful in explaining an interpolation process fora frame boundary row in which no flash band appears. Processes in FIG. 6are carried out by the CPU or the like executing programs stored in theROM or the like of the system control unit 106 and expanded into theRAM. It should be noted that processes in steps S601, S602, and S604 inFIG. 6 are the same as the steps S501, S502, and S504, respectively, inthe first embodiment described above (FIG. 5), and therefore,description thereof is omitted.

Referring to FIG. 6, in the step S603, the system control unit 106determines a time n at which the electronic shutter of the image pickupdevice 102 was turned on for a frame in which the flash band wasdetected in the step S601. Here, when the electronic shutter was notturned on, n=0 holds, and when exposure is performed for a maximum timeperiod while the electronic shutter is kept on, n=1 holds. The greaterthe numeric value of n is, the shorter the exposure time period (shutterspeed) is.

When the system control unit 106 judges that the numeric value of thetime n at which the electronic shutter was turned on is smaller than anarbitrary numeric value m determined in advance, the process proceeds tothe step S604, in which the system control unit 106 in turn carries outan interpolation process for the frame boundary row in the full-screenflash image obtained in the step S602 and ends the process. When thenumeric value of the time n at which the electronic shutter was turnedon is equal to or greater than the numeric value m, that is, when theexposure time period is shorter than the numeric value m, the systemcontrol unit 106 ends the process without carrying out the interpolationprocess since the full-screen flash image would cause increaseddiscomfort due to the interpolation process for the frame boundary rowin the full-screen flash image. It should be noted that the numericvalue m is a value determined in advance as a value at which it ispossible to output an image with no discomfort irrespective of whetherthe electronic shutter is on or off.

As described above, in the present embodiment, when the electronicshutter is on, the interpolation process for the frame boundary row inthe full-screen flash image is not carried out, depending on the time nat which the electronic shutter was turned on, and as a result, an imagewith no discomfort is output. The other constructions and operationaladvantages are the same as those in the first embodiment describedabove.

Referring next to FIG. 7, a description will be given of a digital videocamera that is a third embodiment of the image pickup apparatusaccording to the present invention. It should be noted that for elementscorresponding to those of the first and second embodiments describedabove, the same figures and reference symbols are used in the followingdescription of the present embodiment.

Referring to FIG. 4B, when an average luminance value of the correctedimage or an average luminance value of the frame boundary row is large,the corrected image causes no discomfort since there is only a smalldifference between the region C and the region B′. For this reason, inthe present embodiment, when an average luminance value of the correctedimage or an average luminance value of the frame boundary row is greaterthan a value determined in advance, control is provided so as not tocarry out an interpolation process for the frame boundary row in whichno flash band appears.

FIG. 7 is a flowchart useful in explaining an interpolation process fora frame boundary row in which no flash band appears. Processes in FIG. 7are carried out by the CPU or the like executing programs stored in theROM or the like of the system control unit 106 and expanded into theRAM. It should be noted that processes in steps S701 to S703 and S705 inFIG. 7 are the same as the steps S601 to S603 and S604, respectively, inthe second embodiment described above (FIG. 6), and therefore,description thereof is omitted.

Referring to FIG. 7, when the system control unit 106 judges in the stepS703 that the numeric value of the time n at which the electronicshutter was turned on is smaller than the arbitrary numeric value mdetermined in advance, the process proceeds to the step S704. In thestep S704, the system control unit 106 calculates an average luminancevalue of the corrected image generated in the step S702 (or an averageluminance value of the frame boundary row) and determines whether or notthe calculated average luminance value is greater than an arbitraryvalue X [LSB] determined in advance.

When the average luminance value is not greater than the value X, thesystem control unit 106 determines that the full-screen flash imagecauses discomfort, and the process proceeds to the step S705, in whichthe system control unit 106 in turn carries out the interpolationprocess for the frame boundary row, and when the average luminance valueis greater than the value X, the system control unit 106 ends theprocess without carrying out the interpolation process. It should benoted that although in the present embodiment, the average luminancevalue of the entire corrected image or the frame boundary row is takenas an example, an average luminance value of an arbitrary region may beused. Also, the value X above is a value determined in advance as avalue at which it is possible to output an image with no discomfortirrespective of whether the electronic shutter is on or off.

Thus, in the present embodiment, when an average luminance value of acorrected image or the like is greater than the predetermined value X,it is possible to output an image with no discomfort without carryingout the interpolation process. The other constructions and operationaladvantages are the same as those in the first and second embodimentsdescribed above.

OTHER EMBODIMENTS

Embodiment(s) of the present invention can also be realized by acomputer of a system or apparatus that reads out and executes computerexecutable instructions (e.g., one or more programs) recorded on astorage medium (which may also be referred to more fully as a‘non-transitory computer-readable storage medium’) to perform thefunctions of one or more of the above-described embodiment(s) and/orthat includes one or more circuits (e.g., application specificintegrated circuit (ASIC)) for performing the functions of one or moreof the above-described embodiment(s), and by a method performed by thecomputer of the system or apparatus by, for example, reading out andexecuting the computer executable instructions from the storage mediumto perform the functions of one or more of the above-describedembodiment(s) and/or controlling the one or more circuits to perform thefunctions of one or more of the above-described embodiment(s). Thecomputer may comprise one or more processors (e.g., central processingunit (CPU), micro processing unit (MPU)) and may include a network ofseparate computers or separate processors to read out and execute thecomputer executable instructions. The computer executable instructionsmay be provided to the computer, for example, from a network or thestorage medium. The storage medium may include, for example, one or moreof a hard disk, a random-access memory (RAM), a read only memory (ROM),a storage of distributed computing systems, an optical disk (such as acompact disc (CD), digital versatile disc (DVD), or Blu-ray Disc (BD)™),a flash memory device, a memory card, and the like.

While the present invention has been described with reference toexemplary embodiments, it is to be understood that the invention is notlimited to the disclosed exemplary embodiments. The scope of thefollowing claims is to be accorded the broadest interpretation so as toencompass all such modifications and equivalent structures andfunctions.

This application claims the benefit of Japanese Patent Application No.2016-118924, filed Jun. 15, 2016 which is hereby incorporated byreference herein in its entirety.

What is claimed is:
 1. An image pickup apparatus comprising: an imagepickup device configured to sequentially start exposure and sequentiallyread out signals for each row of pixels; and at least one processor orcircuit configured to function as the following units: a detection unitconfigured to, based on an image signal output from the image pickupdevice, detect a flash band that appears in a plurality of framesconsecutive in terms of time due to an external flash; and a correctionunit configured to correct an image in at least one of the plurality offrames in which the flash band was detected by the detection unit to afull-screen flash image; wherein the correction unit interpolates a rowin which the flash band does not appear using a row in which the flashband appears and which immediately precedes or immediately succeeds therow in which the flash band does not appear.
 2. The image pickupapparatus according to claim 1, wherein the correction unit determineswhether to interpolate the row in which the flash band does not appearaccording to whether an electronic shutter of the image pickup device ison.
 3. The image pickup apparatus according to claim 2, wherein thecorrection unit does not interpolate the row in which the flash banddoes not appear in a case where the electronic shutter of the imagepickup device is not on.
 4. The image pickup apparatus according toclaim 1, wherein the correction unit determines whether to interpolatethe row in which the flash band does not appear according to whether theexternal flash is fired within a time period over which an electronicshutter of the image pickup device is on.
 5. The image pickup apparatusaccording to claim 1, wherein at least the one processor or the circuitis configured to function as a determination unit configured todetermine whether a width of the flash band detected by the detectionunit is equal to or greater than the number of rows in one frame, andwherein when the determination unit determines that the width of theflash band is not equal to or greater than the number of rows in oneframe, the correction unit interpolates the row in which the flash banddoes not appear using the row in which the flash band appears and whichimmediately precedes or immediately succeeds the row in which the flashband does not appear.
 6. The image pickup apparatus according to claim5, wherein according to whether the external flash is fired within atime period over which the electronic shutter of the image pickup deviceis on, the determination unit determines whether the width of the flashband is equal to or greater than the number of rows in one frame.
 7. Theimage pickup apparatus according to claim 1, wherein when a position atwhich an electronic shutter of the image pickup device was turned on issuch a position that an exposure time period of the image pickup deviceis shorter than a value determined in advance, the correction unit doesnot interpolate the row in which the flash band does not appear.
 8. Theimage pickup apparatus according to claim 1, wherein when an averageluminance value of the corrected image is greater than a valuedetermined in advance, the correction unit does not interpolate the rowin which the flash band does not appear.
 9. The image pickup apparatusaccording to claim 8, wherein the average luminance value of thecorrected image is an average luminance value of the corrected image asa whole or an average luminance value in a row at a boundary between therow in which the flash band appears and the row in which the flash banddoes not appear.
 10. The image pickup apparatus according to claim 1,wherein the correction unit interpolates the row in which the flash banddoes not appear by copying a row in which the flash band appears andwhich immediately precedes or immediately succeeds the row in which theflash band does not appear.
 11. The image pickup apparatus according toclaim 1, wherein the correction unit interpolates the row in which theflash band does not appear by averaging rows in which the flash bandappears and which immediately precede and immediately succeed the row inwhich the flash band does not appear.
 12. A video processing apparatusthat corrects a video comprising a plurality of frames, comprising: atleast one processor or circuit configured to function as the followingunits: a detection unit configured to detect a flash band that appearsin a plurality of frames consecutive in terms of time among theplurality of frames; a correction unit configured to correct an image inat least one of the plurality of frames in which the flash band wasdetected to a flash image by combining regions where the flash bandappears in respective ones of the plurality of frames in which the flashband was detected; and an output unit configured to output a videocorrected by the correction unit, wherein the correction unitinterpolates an image in a row at a boundary of the flash band usingimage data in the region where the flash band appears.
 13. The videoprocessing apparatus according to claim 12, wherein when a total numberof rows in a region where the flash band appears in the plurality offrames in which the flash band was detected is smaller than the numberof frames in one frame, the correction unit interpolates the image inthe row at the boundary of the flash band using the image data in theregion where the flash band appears.
 14. The video processing apparatusaccording to claim 12, wherein the correction unit interpolates the rowat the boundary of the flash band by copying a row in which the flashband appears and which immediately precedes or immediately succeeds therow at the boundary of the flash band.
 15. The video processingapparatus according to claim 12, wherein the correction unitinterpolates the row at the boundary of the flash band by averaging rowsin which the flash band appears and which immediately precede andimmediately succeed the row at the boundary of the flash band.
 16. Acontrol method for an image pickup apparatus with an image pickup devicethat sequentially starts exposure and sequentially reads out signals foreach row of pixels, comprising: a detection step of, based on an imagesignal output from the image pickup device, detecting a flash band thatappears in a plurality of frames consecutive in terms of time due to anexternal flash; and a correction step of correcting an image in at leastone of the plurality of frames in which the flash band was detected inthe detection step to a full-screen flash image; wherein a row in whichthe flash band does not appear is interpolated using a row in which theflash band appears and which immediately precedes or immediatelysucceeds the row in which the flash band does not appear.
 17. A controlmethod for a video processing apparatus that corrects a video comprisinga plurality of frames, comprising: a detection step of detecting a flashband that appears in a plurality of frames consecutive in terms of timeamong the plurality of frames; a correction step of correcting an imagein at least one of the plurality of frames in which the flash band wasdetected to a flash image by combining regions where the flash bandappears in respective ones of the plurality of frames in which the flashband was detected; and an output step of outputting a video corrected inthe correction step, wherein an image in a row at a boundary of theflash band is interpolated using image data in the region where theflash band appears.
 18. A non-transitory computer-readable storagemedium storing a program for causing a computer to execute a controlmethod for an image pickup apparatus with an image pickup device thatsequentially starts exposure and sequentially reads out signals for eachrow of pixels, the control method comprising: a detection step of, basedon an image signal output from the image pickup device, detecting aflash band that appears in a plurality of frames consecutive in terms oftime due to an external flash; and a correction step of correcting animage in at least one of the plurality of frames in which the flash bandwas detected in the detection step to a full-screen flash image; whereina row in which the flash band does not appear is interpolated using arow in which the flash band appears and which immediately precedes orimmediately succeeds the row in which the flash band does not appear.19. A non-transitory computer-readable storage medium storing a programfor causing a computer to execute a control method for a videoprocessing apparatus that corrects a video comprising a plurality offrames, the control method comprising: a detection step of detecting aflash band that appears in a plurality of frames consecutive in terms oftime among the plurality of frames; a correction step of correcting animage in at least one of the plurality of frames in which the flash bandwas detected to a flash image by combining regions where the flash bandappears in respective ones of the plurality of frames in which the flashband was detected; and an output step of outputting a video corrected inthe correction step, wherein an image in a row at a boundary of theflash band is interpolated using image data in the region where theflash band appears.